Most of the times iTunes Match works fine, when it does not work then it is a head ache. There are numerous synchronization problems, each require a different solution. Here we are trying to give solutions to few of the problems.
Blocking iTunes Match in step 1 of the synchronization is a classic. Sometimes the blockage is only apparent; let your machine run all night, and you will notice that the progress bar has moved slowly. Better to let iTunes Match to take its own time rather than cutting and start syncing, so you should solve your troubles patiently.
ITunes tells you if an error 4010 and suggest you try later, follow its advice; things will be set right in the second or third try. Blockage persists sometimes, but perhaps most of the time set by resetting the identifier your library on Apple's servers to force synchronization "clean." To do this, simply select the Store menu> Disable iTunes Match while maintaining ⌥ key, then select Store> Turn on iTunes Match.
If you're still stuck at step 1 after these manipulations, it becomes more difficult to find the exact cause. Cuts in the view, display layout options (View> View Options) and check the status iCloud. Sort the column that appears to reveal the errors and try to find common ground at there. On the Summary tab, check the origin of particular pieces: whether they were purchased with another account, it is possible that you are no longer allowed to read. If you can, allow your computer to read the contents of the account in question (Store> Authorize this computer after you are connected to the account).
It also appears that iTunes Match lost more easily when using the pedals several different file formats, even if it is supposed to manage, among other things, AAC, MP3, WAV, AIFF and ALAC. If possible, do not hesitate to convert your files to get a more coherent library: according to our tests, iTunes Match is much more stable with two formats AAC and ALAC for example. You choose the format in the Import Settings panel in the General section of iTunes preferences and then converts with File> Conversion.
Create a list of similar reading (File> New> Smart Playlist) to list all the songs in a certain format and thus easily convert. You can then delete the duplicates and multiple entries.